A number of 120 human endometrial samples will be studied, and will be collected from 40 infertile women attending the infertility clinic at NRC. Each human endometrial sample will be divided into 3 plates, in order to establish 3 main groups of 40 culture plates for single laser exposure group versus 40 culture plates for multiple laser exposure group and 40 tissue culture plates for control samples, thus a total of 120 tissue culture plates will be studied, the study groups will be exposed to low level laser therapy and compared to their matched controls.. Assessment of number and size of cells after LLLT as a marker of normal proliferation and b) The expression of Integrin aVB3 "alpha v B3", MUC-1 and LIFand the development of pinopodes on the surface of epithelial cells as markers of endometrial receptivity and the detection of PTEN tumor suppressor gene as a marker of abnormal proliferation or premalignant condition will be performed to assess the effect of LLLT on the endometrial cell culture. This study might offer a new therapeutic modality which might increase endometrial thickness and enhance receptivity .